From 067e68e7041ec6eff73dd053876e22eaf1d4cb00 Mon Sep 17 00:00:00 2001 From: Andrey Smirnov Date: Fri, 9 Feb 2018 10:40:29 +0000 Subject: [PATCH] i.MX: Add code to emulate i.MX2 watchdog IP block MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Add enough code to emulate i.MX2 watchdog IP block so it would be possible to reboot the machine running Linux Guest. Cc: Peter Maydell Cc: Jason Wang Cc: Philippe Mathieu-Daudé Cc: Marcel Apfelbaum Cc: Michael S. Tsirkin Cc: qemu-devel@nongnu.org Cc: qemu-arm@nongnu.org Cc: yurovsky@gmail.com Reviewed-by: Peter Maydell Signed-off-by: Andrey Smirnov Reviewed-by: Philippe Mathieu-Daudé Signed-off-by: Peter Maydell --- hw/misc/Makefile.objs | 1 + hw/misc/imx2_wdt.c | 89 ++++++++++++++++++++++++++++++++++++++ include/hw/misc/imx2_wdt.h | 33 ++++++++++++++ 3 files changed, 123 insertions(+) create mode 100644 hw/misc/imx2_wdt.c create mode 100644 include/hw/misc/imx2_wdt.h diff --git a/hw/misc/Makefile.objs b/hw/misc/Makefile.objs index a28e5e49b0..4b2b705a6c 100644 --- a/hw/misc/Makefile.objs +++ b/hw/misc/Makefile.objs @@ -34,6 +34,7 @@ obj-$(CONFIG_IMX) += imx25_ccm.o obj-$(CONFIG_IMX) += imx6_ccm.o obj-$(CONFIG_IMX) += imx6_src.o obj-$(CONFIG_IMX) += imx7_ccm.o +obj-$(CONFIG_IMX) += imx2_wdt.o obj-$(CONFIG_MILKYMIST) += milkymist-hpdmc.o obj-$(CONFIG_MILKYMIST) += milkymist-pfpu.o obj-$(CONFIG_MAINSTONE) += mst_fpga.o diff --git a/hw/misc/imx2_wdt.c b/hw/misc/imx2_wdt.c new file mode 100644 index 0000000000..e47e442592 --- /dev/null +++ b/hw/misc/imx2_wdt.c @@ -0,0 +1,89 @@ +/* + * Copyright (c) 2018, Impinj, Inc. + * + * i.MX2 Watchdog IP block + * + * Author: Andrey Smirnov + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#include "qemu/osdep.h" +#include "qemu/bitops.h" +#include "sysemu/watchdog.h" + +#include "hw/misc/imx2_wdt.h" + +#define IMX2_WDT_WCR_WDA BIT(5) /* -> External Reset WDOG_B */ +#define IMX2_WDT_WCR_SRS BIT(4) /* -> Software Reset Signal */ + +static uint64_t imx2_wdt_read(void *opaque, hwaddr addr, + unsigned int size) +{ + return 0; +} + +static void imx2_wdt_write(void *opaque, hwaddr addr, + uint64_t value, unsigned int size) +{ + if (addr == IMX2_WDT_WCR && + (value & (IMX2_WDT_WCR_WDA | IMX2_WDT_WCR_SRS))) { + watchdog_perform_action(); + } +} + +static const MemoryRegionOps imx2_wdt_ops = { + .read = imx2_wdt_read, + .write = imx2_wdt_write, + .endianness = DEVICE_NATIVE_ENDIAN, + .impl = { + /* + * Our device would not work correctly if the guest was doing + * unaligned access. This might not be a limitation on the + * real device but in practice there is no reason for a guest + * to access this device unaligned. + */ + .min_access_size = 4, + .max_access_size = 4, + .unaligned = false, + }, +}; + +static void imx2_wdt_realize(DeviceState *dev, Error **errp) +{ + IMX2WdtState *s = IMX2_WDT(dev); + + memory_region_init_io(&s->mmio, OBJECT(dev), + &imx2_wdt_ops, s, + TYPE_IMX2_WDT".mmio", + IMX2_WDT_REG_NUM * sizeof(uint16_t)); + sysbus_init_mmio(SYS_BUS_DEVICE(dev), &s->mmio); +} + +static void imx2_wdt_class_init(ObjectClass *klass, void *data) +{ + DeviceClass *dc = DEVICE_CLASS(klass); + + dc->realize = imx2_wdt_realize; + set_bit(DEVICE_CATEGORY_MISC, dc->categories); +} + +static const TypeInfo imx2_wdt_info = { + .name = TYPE_IMX2_WDT, + .parent = TYPE_SYS_BUS_DEVICE, + .instance_size = sizeof(IMX2WdtState), + .class_init = imx2_wdt_class_init, +}; + +static WatchdogTimerModel model = { + .wdt_name = "imx2-watchdog", + .wdt_description = "i.MX2 Watchdog", +}; + +static void imx2_wdt_register_type(void) +{ + watchdog_add_model(&model); + type_register_static(&imx2_wdt_info); +} +type_init(imx2_wdt_register_type) diff --git a/include/hw/misc/imx2_wdt.h b/include/hw/misc/imx2_wdt.h new file mode 100644 index 0000000000..8afc99a10e --- /dev/null +++ b/include/hw/misc/imx2_wdt.h @@ -0,0 +1,33 @@ +/* + * Copyright (c) 2017, Impinj, Inc. + * + * i.MX2 Watchdog IP block + * + * Author: Andrey Smirnov + * + * This work is licensed under the terms of the GNU GPL, version 2 or later. + * See the COPYING file in the top-level directory. + */ + +#ifndef IMX2_WDT_H +#define IMX2_WDT_H + +#include "hw/sysbus.h" + +#define TYPE_IMX2_WDT "imx2.wdt" +#define IMX2_WDT(obj) OBJECT_CHECK(IMX2WdtState, (obj), TYPE_IMX2_WDT) + +enum IMX2WdtRegisters { + IMX2_WDT_WCR = 0x0000, + IMX2_WDT_REG_NUM = 0x0008 / sizeof(uint16_t) + 1, +}; + + +typedef struct IMX2WdtState { + /* */ + SysBusDevice parent_obj; + + MemoryRegion mmio; +} IMX2WdtState; + +#endif /* IMX7_SNVS_H */